linux/arch/sh/kernel/process_64.c
Linus Torvalds 221af7f87b Split 'flush_old_exec' into two functions
'flush_old_exec()' is the point of no return when doing an execve(), and
it is pretty badly misnamed.  It doesn't just flush the old executable
environment, it also starts up the new one.

Which is very inconvenient for things like setting up the new
personality, because we want the new personality to affect the starting
of the new environment, but at the same time we do _not_ want the new
personality to take effect if flushing the old one fails.

As a result, the x86-64 '32-bit' personality is actually done using this
insane "I'm going to change the ABI, but I haven't done it yet" bit
(TIF_ABI_PENDING), with SET_PERSONALITY() not actually setting the
personality, but just the "pending" bit, so that "flush_thread()" can do
the actual personality magic.

This patch in no way changes any of that insanity, but it does split the
'flush_old_exec()' function up into a preparatory part that can fail
(still called flush_old_exec()), and a new part that will actually set
up the new exec environment (setup_new_exec()).  All callers are changed
to trivially comply with the new world order.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-29 08:22:01 -08:00

578 lines
16 KiB
C

/*
* arch/sh/kernel/process_64.c
*
* This file handles the architecture-dependent parts of process handling..
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003 - 2007 Paul Mundt
* Copyright (C) 2003, 2004 Richard Curnow
*
* Started from SH3/4 version:
* Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
*
* In turn started from i386 version:
* Copyright (C) 1995 Linus Torvalds
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/ptrace.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/io.h>
#include <asm/syscalls.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/mmu_context.h>
#include <asm/fpu.h>
struct task_struct *last_task_used_math = NULL;
void machine_restart(char * __unused)
{
extern void phys_stext(void);
phys_stext();
}
void machine_halt(void)
{
for (;;);
}
void machine_power_off(void)
{
__asm__ __volatile__ (
"sleep\n\t"
"synci\n\t"
"nop;nop;nop;nop\n\t"
);
panic("Unexpected wakeup!\n");
}
void show_regs(struct pt_regs * regs)
{
unsigned long long ah, al, bh, bl, ch, cl;
printk("\n");
ah = (regs->pc) >> 32;
al = (regs->pc) & 0xffffffff;
bh = (regs->regs[18]) >> 32;
bl = (regs->regs[18]) & 0xffffffff;
ch = (regs->regs[15]) >> 32;
cl = (regs->regs[15]) & 0xffffffff;
printk("PC : %08Lx%08Lx LINK: %08Lx%08Lx SP : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->sr) >> 32;
al = (regs->sr) & 0xffffffff;
asm volatile ("getcon " __TEA ", %0" : "=r" (bh));
asm volatile ("getcon " __TEA ", %0" : "=r" (bl));
bh = (bh) >> 32;
bl = (bl) & 0xffffffff;
asm volatile ("getcon " __KCR0 ", %0" : "=r" (ch));
asm volatile ("getcon " __KCR0 ", %0" : "=r" (cl));
ch = (ch) >> 32;
cl = (cl) & 0xffffffff;
printk("SR : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[0]) >> 32;
al = (regs->regs[0]) & 0xffffffff;
bh = (regs->regs[1]) >> 32;
bl = (regs->regs[1]) & 0xffffffff;
ch = (regs->regs[2]) >> 32;
cl = (regs->regs[2]) & 0xffffffff;
printk("R0 : %08Lx%08Lx R1 : %08Lx%08Lx R2 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[3]) >> 32;
al = (regs->regs[3]) & 0xffffffff;
bh = (regs->regs[4]) >> 32;
bl = (regs->regs[4]) & 0xffffffff;
ch = (regs->regs[5]) >> 32;
cl = (regs->regs[5]) & 0xffffffff;
printk("R3 : %08Lx%08Lx R4 : %08Lx%08Lx R5 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[6]) >> 32;
al = (regs->regs[6]) & 0xffffffff;
bh = (regs->regs[7]) >> 32;
bl = (regs->regs[7]) & 0xffffffff;
ch = (regs->regs[8]) >> 32;
cl = (regs->regs[8]) & 0xffffffff;
printk("R6 : %08Lx%08Lx R7 : %08Lx%08Lx R8 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[9]) >> 32;
al = (regs->regs[9]) & 0xffffffff;
bh = (regs->regs[10]) >> 32;
bl = (regs->regs[10]) & 0xffffffff;
ch = (regs->regs[11]) >> 32;
cl = (regs->regs[11]) & 0xffffffff;
printk("R9 : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[12]) >> 32;
al = (regs->regs[12]) & 0xffffffff;
bh = (regs->regs[13]) >> 32;
bl = (regs->regs[13]) & 0xffffffff;
ch = (regs->regs[14]) >> 32;
cl = (regs->regs[14]) & 0xffffffff;
printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[16]) >> 32;
al = (regs->regs[16]) & 0xffffffff;
bh = (regs->regs[17]) >> 32;
bl = (regs->regs[17]) & 0xffffffff;
ch = (regs->regs[19]) >> 32;
cl = (regs->regs[19]) & 0xffffffff;
printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[20]) >> 32;
al = (regs->regs[20]) & 0xffffffff;
bh = (regs->regs[21]) >> 32;
bl = (regs->regs[21]) & 0xffffffff;
ch = (regs->regs[22]) >> 32;
cl = (regs->regs[22]) & 0xffffffff;
printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[23]) >> 32;
al = (regs->regs[23]) & 0xffffffff;
bh = (regs->regs[24]) >> 32;
bl = (regs->regs[24]) & 0xffffffff;
ch = (regs->regs[25]) >> 32;
cl = (regs->regs[25]) & 0xffffffff;
printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[26]) >> 32;
al = (regs->regs[26]) & 0xffffffff;
bh = (regs->regs[27]) >> 32;
bl = (regs->regs[27]) & 0xffffffff;
ch = (regs->regs[28]) >> 32;
cl = (regs->regs[28]) & 0xffffffff;
printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[29]) >> 32;
al = (regs->regs[29]) & 0xffffffff;
bh = (regs->regs[30]) >> 32;
bl = (regs->regs[30]) & 0xffffffff;
ch = (regs->regs[31]) >> 32;
cl = (regs->regs[31]) & 0xffffffff;
printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[32]) >> 32;
al = (regs->regs[32]) & 0xffffffff;
bh = (regs->regs[33]) >> 32;
bl = (regs->regs[33]) & 0xffffffff;
ch = (regs->regs[34]) >> 32;
cl = (regs->regs[34]) & 0xffffffff;
printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[35]) >> 32;
al = (regs->regs[35]) & 0xffffffff;
bh = (regs->regs[36]) >> 32;
bl = (regs->regs[36]) & 0xffffffff;
ch = (regs->regs[37]) >> 32;
cl = (regs->regs[37]) & 0xffffffff;
printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[38]) >> 32;
al = (regs->regs[38]) & 0xffffffff;
bh = (regs->regs[39]) >> 32;
bl = (regs->regs[39]) & 0xffffffff;
ch = (regs->regs[40]) >> 32;
cl = (regs->regs[40]) & 0xffffffff;
printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[41]) >> 32;
al = (regs->regs[41]) & 0xffffffff;
bh = (regs->regs[42]) >> 32;
bl = (regs->regs[42]) & 0xffffffff;
ch = (regs->regs[43]) >> 32;
cl = (regs->regs[43]) & 0xffffffff;
printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[44]) >> 32;
al = (regs->regs[44]) & 0xffffffff;
bh = (regs->regs[45]) >> 32;
bl = (regs->regs[45]) & 0xffffffff;
ch = (regs->regs[46]) >> 32;
cl = (regs->regs[46]) & 0xffffffff;
printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[47]) >> 32;
al = (regs->regs[47]) & 0xffffffff;
bh = (regs->regs[48]) >> 32;
bl = (regs->regs[48]) & 0xffffffff;
ch = (regs->regs[49]) >> 32;
cl = (regs->regs[49]) & 0xffffffff;
printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[50]) >> 32;
al = (regs->regs[50]) & 0xffffffff;
bh = (regs->regs[51]) >> 32;
bl = (regs->regs[51]) & 0xffffffff;
ch = (regs->regs[52]) >> 32;
cl = (regs->regs[52]) & 0xffffffff;
printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[53]) >> 32;
al = (regs->regs[53]) & 0xffffffff;
bh = (regs->regs[54]) >> 32;
bl = (regs->regs[54]) & 0xffffffff;
ch = (regs->regs[55]) >> 32;
cl = (regs->regs[55]) & 0xffffffff;
printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[56]) >> 32;
al = (regs->regs[56]) & 0xffffffff;
bh = (regs->regs[57]) >> 32;
bl = (regs->regs[57]) & 0xffffffff;
ch = (regs->regs[58]) >> 32;
cl = (regs->regs[58]) & 0xffffffff;
printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[59]) >> 32;
al = (regs->regs[59]) & 0xffffffff;
bh = (regs->regs[60]) >> 32;
bl = (regs->regs[60]) & 0xffffffff;
ch = (regs->regs[61]) >> 32;
cl = (regs->regs[61]) & 0xffffffff;
printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->regs[62]) >> 32;
al = (regs->regs[62]) & 0xffffffff;
bh = (regs->tregs[0]) >> 32;
bl = (regs->tregs[0]) & 0xffffffff;
ch = (regs->tregs[1]) >> 32;
cl = (regs->tregs[1]) & 0xffffffff;
printk("R62 : %08Lx%08Lx T0 : %08Lx%08Lx T1 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->tregs[2]) >> 32;
al = (regs->tregs[2]) & 0xffffffff;
bh = (regs->tregs[3]) >> 32;
bl = (regs->tregs[3]) & 0xffffffff;
ch = (regs->tregs[4]) >> 32;
cl = (regs->tregs[4]) & 0xffffffff;
printk("T2 : %08Lx%08Lx T3 : %08Lx%08Lx T4 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
ah = (regs->tregs[5]) >> 32;
al = (regs->tregs[5]) & 0xffffffff;
bh = (regs->tregs[6]) >> 32;
bl = (regs->tregs[6]) & 0xffffffff;
ch = (regs->tregs[7]) >> 32;
cl = (regs->tregs[7]) & 0xffffffff;
printk("T5 : %08Lx%08Lx T6 : %08Lx%08Lx T7 : %08Lx%08Lx\n",
ah, al, bh, bl, ch, cl);
/*
* If we're in kernel mode, dump the stack too..
*/
if (!user_mode(regs)) {
void show_stack(struct task_struct *tsk, unsigned long *sp);
unsigned long sp = regs->regs[15] & 0xffffffff;
struct task_struct *tsk = get_current();
tsk->thread.kregs = regs;
show_stack(tsk, (unsigned long *)sp);
}
}
/*
* Create a kernel thread
*/
ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *))
{
do_exit(fn(arg));
}
/*
* This is the mechanism for creating a new kernel thread.
*
* NOTE! Only a kernel-only process(ie the swapper or direct descendants
* who haven't done an "execve()") should use this: it will work within
* a system call from a "real" process, but the process memory space will
* not be freed until both the parent and the child have exited.
*/
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
struct pt_regs regs;
memset(&regs, 0, sizeof(regs));
regs.regs[2] = (unsigned long)arg;
regs.regs[3] = (unsigned long)fn;
regs.pc = (unsigned long)kernel_thread_helper;
regs.sr = (1 << 30);
/* Ok, create the new process.. */
return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
&regs, 0, NULL, NULL);
}
EXPORT_SYMBOL(kernel_thread);
/*
* Free current thread data structures etc..
*/
void exit_thread(void)
{
/*
* See arch/sparc/kernel/process.c for the precedent for doing
* this -- RPC.
*
* The SH-5 FPU save/restore approach relies on
* last_task_used_math pointing to a live task_struct. When
* another task tries to use the FPU for the 1st time, the FPUDIS
* trap handling (see arch/sh/kernel/cpu/sh5/fpu.c) will save the
* existing FPU state to the FP regs field within
* last_task_used_math before re-loading the new task's FPU state
* (or initialising it if the FPU has been used before). So if
* last_task_used_math is stale, and its page has already been
* re-allocated for another use, the consequences are rather
* grim. Unless we null it here, there is no other path through
* which it would get safely nulled.
*/
#ifdef CONFIG_SH_FPU
if (last_task_used_math == current) {
last_task_used_math = NULL;
}
#endif
}
void flush_thread(void)
{
/* Called by fs/exec.c (setup_new_exec) to remove traces of a
* previously running executable. */
#ifdef CONFIG_SH_FPU
if (last_task_used_math == current) {
last_task_used_math = NULL;
}
/* Force FPU state to be reinitialised after exec */
clear_used_math();
#endif
/* if we are a kernel thread, about to change to user thread,
* update kreg
*/
if(current->thread.kregs==&fake_swapper_regs) {
current->thread.kregs =
((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
current->thread.uregs = current->thread.kregs;
}
}
void release_thread(struct task_struct *dead_task)
{
/* do nothing */
}
/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
{
#ifdef CONFIG_SH_FPU
int fpvalid;
struct task_struct *tsk = current;
fpvalid = !!tsk_used_math(tsk);
if (fpvalid) {
if (current == last_task_used_math) {
enable_fpu();
save_fpu(tsk);
disable_fpu();
last_task_used_math = 0;
regs->sr |= SR_FD;
}
memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
}
return fpvalid;
#else
return 0; /* Task didn't use the fpu at all. */
#endif
}
EXPORT_SYMBOL(dump_fpu);
asmlinkage void ret_from_fork(void);
int copy_thread(unsigned long clone_flags, unsigned long usp,
unsigned long unused,
struct task_struct *p, struct pt_regs *regs)
{
struct pt_regs *childregs;
#ifdef CONFIG_SH_FPU
if(last_task_used_math == current) {
enable_fpu();
save_fpu(current);
disable_fpu();
last_task_used_math = NULL;
regs->sr |= SR_FD;
}
#endif
/* Copy from sh version */
childregs = (struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1;
*childregs = *regs;
/*
* Sign extend the edited stack.
* Note that thread.pc and thread.pc will stay
* 32-bit wide and context switch must take care
* of NEFF sign extension.
*/
if (user_mode(regs)) {
childregs->regs[15] = neff_sign_extend(usp);
p->thread.uregs = childregs;
} else {
childregs->regs[15] =
neff_sign_extend((unsigned long)task_stack_page(p) +
THREAD_SIZE);
}
childregs->regs[9] = 0; /* Set return value for child */
childregs->sr |= SR_FD; /* Invalidate FPU flag */
p->thread.sp = (unsigned long) childregs;
p->thread.pc = (unsigned long) ret_from_fork;
return 0;
}
asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs *pregs)
{
return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
}
asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs *pregs)
{
if (!newsp)
newsp = pregs->regs[15];
return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
}
/*
* This is trivial, and on the face of it looks like it
* could equally well be done in user mode.
*
* Not so, for quite unobvious reasons - register pressure.
* In user mode vfork() cannot have a stack frame, and if
* done by calling the "clone()" system call directly, you
* do not have enough call-clobbered registers to hold all
* the information you need.
*/
asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs *pregs)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
}
/*
* sys_execve() executes a new program.
*/
asmlinkage int sys_execve(char *ufilename, char **uargv,
char **uenvp, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs *pregs)
{
int error;
char *filename;
filename = getname((char __user *)ufilename);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename,
(char __user * __user *)uargv,
(char __user * __user *)uenvp,
pregs);
putname(filename);
out:
return error;
}
/*
* These bracket the sleeping functions..
*/
extern void interruptible_sleep_on(wait_queue_head_t *q);
#define mid_sched ((unsigned long) interruptible_sleep_on)
#ifdef CONFIG_FRAME_POINTER
static int in_sh64_switch_to(unsigned long pc)
{
extern char __sh64_switch_to_end;
/* For a sleeping task, the PC is somewhere in the middle of the function,
so we don't have to worry about masking the LSB off */
return (pc >= (unsigned long) sh64_switch_to) &&
(pc < (unsigned long) &__sh64_switch_to_end);
}
#endif
unsigned long get_wchan(struct task_struct *p)
{
unsigned long pc;
if (!p || p == current || p->state == TASK_RUNNING)
return 0;
/*
* The same comment as on the Alpha applies here, too ...
*/
pc = thread_saved_pc(p);
#ifdef CONFIG_FRAME_POINTER
if (in_sh64_switch_to(pc)) {
unsigned long schedule_fp;
unsigned long sh64_switch_to_fp;
unsigned long schedule_caller_pc;
sh64_switch_to_fp = (long) p->thread.sp;
/* r14 is saved at offset 4 in the sh64_switch_to frame */
schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);
/* and the caller of 'schedule' is (currently!) saved at offset 24
in the frame of schedule (from disasm) */
schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
return schedule_caller_pc;
}
#endif
return pc;
}